Conventionally, one aspect of a static fluid mixer includes the one in which: a disk-shaped second mixing element is disposed to be opposed to a disk-shaped first mixing element forming a flow inlet of fluid at a center part thereof; and between the mixing elements, a mixing flow path is formed through which the fluid having flown from the flow inlet to between both the mixing elements flows. In addition, the mixing flow path is provided with: a plurality of diverting parts adapted to flow and divert the fluid having flown from the flow inlet in a radiation direction; and a plurality of converging parts adapted to flow in a radiation direction and merge the fluid having been diverted at the diverting parts. Further, a flow outlet formed at the second mixing element is allowed to communicate with a trailer part of the mixing flow path, and the flow outlet is formed by punching a plenty of small-diameter circular holes at intervals in a circumferential direction.
An annular seal part is interposed between junction parts joining in a facial contact state at the circumferential edge parts of the first and second mixing elements.    Patent Document 1: Publication WO2002/070117